Oil pan and engine assembly including the oil pan

ABSTRACT

An engine assembly can heat or cool oil and includes an oil pan. The oil pan includes an oil pan body, and the oil pan body includes an inner pan surface and an outer pan surface opposite the inner pan surface. The inner pan surface defines a cavity configured to collect oil. The oil pan further includes a pan passageway extending through the oil pan body. The pan passageway is disposed between the inner pan surface and the outer pan surface. In addition, the pan passageway is configured to carry a heat transfer fluid in order to transfer heat between the oil disposed in the cavity of the oil pan and the heat transfer fluid.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/110,770, filed Feb. 2, 2015, which is hereby incorporated byreference in its entirety.

TECHNICAL FIELD

The present disclosure relates to an oil pan and an engine assemblyincluding the oil pan.

BACKGROUND

An oil pan can collect oil used to lubricate an internal combustionengine. During operation of the internal combustion engine, oil maycirculate within the internal combustion engine to lubricate movingcomponents of the internal combustion engine, dissipate thermal energy,and protect against wear of the internal combustion engine. Afterlubricating the moving parts of the engine, the oil is collected by theoil pan.

SUMMARY

To maximize fuel efficiency during operation of an internal combustionengine, the oil lubricating the engine should have an optimum oilviscosity. The oil viscosity can be varied by adjusting the temperatureof the oil. Accordingly, it is useful to heat or cool the oil in the oilpan in order to adjust the oil viscosity. The presently disclosed engineassembly can heat or cool the oil in the oil pan independently of theoil flowrate generated by an oil pump. In an embodiment, the presentlydisclosed engine assembly includes an oil pan, which may be casted. Theoil pan includes an oil pan body, and the oil pan body includes an innerpan surface and an outer pan surface opposite the inner pan surface. Theinner pan surface defines a cavity configured to collect oil. The oilpan further includes a pan passageway (e.g., jacket) extending throughthe oil pan body. The pan passageway is disposed between the inner pansurface and the outer pan surface. In addition, the pan passageway isconfigured to carry a heat transfer fluid (e.g., coolant) in order totransfer heat between the oil disposed in the cavity and the heattransfer fluid. The present disclosure also relates to an oil pan asdescribed above and a method for exchanging heat between the oil in theoil pan and the heat transfer fluid flowing through the pan passageway.

The above features and advantages and other features and advantages ofthe present teachings are readily apparent from the following detaileddescription of the best modes for carrying out the teachings when takenin connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a vehicle including an engineassembly in accordance with an embodiment of the present disclosure,wherein the engine assembly includes an oil pan;

FIG. 2 is a schematic, perspective view of an oil pan shown in FIG. 1;

FIG. 3 is a schematic, top view of the oil pan shown in FIG. 2;

FIG. 4 is a schematic, cross-sectional view of the oil pan shown in FIG.2, taken by the section line 4-4 of FIG. 3; and

FIG. 5 is a flowchart of a method for exchanging heat between a heattransfer fluid and oil in the oil pan shown in FIG. 2.

DETAILED DESCRIPTION

Referring to the drawings, wherein like reference numbers correspond tolike or similar components throughout the several figures, FIG. 1schematically illustrates a vehicle 10, such as a car, including anengine assembly 12. The engine assembly 12 includes an internalcombustion engine 14 configured to propel the vehicle 10. The internalcombustion engine 14 employs oil O for lubrication, among other things.The engine assembly 12 further includes an oil pan 16 coupled to theinternal combustion engine 14. As a consequence, oil O can flow betweenthe internal combustion engine 14 and the oil pan 16. Specifically, theoil O can lubricate the internal combustion engine 14 and then flows tothe oil pan 16. The oil pan 16 then collects the oil O but the oil Odoes not rise above a predetermined oil level L. The engine assembly 12further includes an oil pump 18 coupled to the oil pan 16. Consequently,the oil pump 18 can move the oil O from the oil pan 16 to anothervehicle component 20, such as an oil gallery. The oil O can then flowback from the vehicle component 20 (e.g., oil gallery) to the internalcombustion engine 14.

To maximize fuel efficiency during operation of the internal combustionengine 14, the oil O should have an optimum oil viscosity. The oilviscosity can be varied by adjusting the temperature of the oil O.Accordingly, it is useful to heat or cool the oil O in the oil pan 16 inorder to adjust the oil viscosity. The presently disclosed engineassembly 12 can heat or cool the oil O in the oil pan 16 independentlyof the oil flowrate generated by the oil pump 18. This is especiallyimportant in the scenario when the internal combustion engine 14 iswarming up and the engine speed is relatively low. In this scenario,heating the oil O can decrease its viscosity, thereby minimizingfriction in the internal combustion engine 14. It is projected that, byusing the presently disclosed oil pan 16, the fuel efficiency of theinternal combustion engine 14 can be improved by about one (1) to onepoint five (1.5) percent over conventional engines during the warm upperiod.

The engine assembly 12 further includes a heat transfer fluid source 22capable of holding heat transfer fluid F. The heat transfer fluid F canbe any fluid (e.g., liquid) suitable for transferring heat. As anon-limiting example, the heat transfer fluid F may be a coolant, suchethylene glycol. The fluid source 22 is in fluid communication with aninput passageway 24 (e.g., conduit, tube, pipe, etc.). The inputpassageway 24 is outside the oil pan 16 and is fluidly coupled betweenthe oil pan 16 and the fluid source 22. Accordingly, the heat transferfluid F can flow from the fluid source 22 to the oil pan 16. A fluidtransfer pump 26 is also coupled to the input passageway 24 in order tomove the heat transfer fluid F from the fluid source 22 to the oil pan16 through the input passageway 24.

The input passageway 24 is in thermal communication with a heat source28. As a consequence, the heat source 28 can heat the heat transferfluid F flowing through the input passageway 24. As non-limitingexamples, the heat source 28 can be an exhaust manifold, an exhaust gasrecirculation system, a turbocharger, an engine block, an engine head,or a combination thereof. Regardless of the kind of heat source 28 used,heat H can be transferred between the heat transfer fluid F flowingthrough the input passageway 24 and the heat source 28.

The input passageway 24 is in thermal communication with a coolingsource 30. As a consequence, the cooling source 30 can cool the heattransfer fluid F flowing through the input passageway 24. As anon-limiting example, the cooling source 30 can be the cooling system ofthe vehicle 10. Irrespective of the kind of cooling source 30 used, heatH can be transferred between the heat transfer fluid F flowing throughthe input passageway 24 and the cooling source 30.

As discussed in detail below, the oil pan 16 has a pan passageway 32(e.g., jacket, hole, opening) formed by the oil pan body 36 and in fluidcommunication with the input passageway 24. Accordingly, the heattransfer fluid F can flow between the input passageway 24 and the panpassageway 32. While flowing through the pan passageway 32, heat can betransferred between the oil O disposed in the oil pan 16 and the heattransfer fluid F flowing through the pan passageway 32 as discussedbelow. The engine assembly 12 also includes an output passageway 34(e.g., conduit, tube, pipe, etc.) outside the oil pan 16. The outputpassageway 34 is in fluid communication with the pan passageway 32.Accordingly, the heat transfer fluid F can flow between the panpassageway 32 and the output passageway 34 once heat has beentransferred between the heat transfer fluid F flowing through the panpassageway 32 and the oil O disposed in the oil pan 16. It iscontemplated that the oil pan 16 may include one or more pan passageways32.

With reference to FIGS. 2-3, the oil pan 16 is wholly or partly made ofa substantially rigid material, such as a rigid metallic material, andis configured to hold the oil O. It is contemplated that the oil pan 16can be manufactured by casting. However, other suitable manufacturingmethods can be used to make the oil pan 16. Regardless of themanufacturing method employed, the oil pan 16 includes an oil pan body36 including a plurality of walls 38. For example, in the depictedembodiment, the oil pan 16 includes a plurality of sidewalls 38 a and atleast one bottom wall 38 b interconnecting the sidewalls 38 a. The oilpan body 36 defines an inner pan surface 40 and an outer pan surface 42opposite the inner pan surface 40. The inner pan surface 40 defines anopen cavity 44 configured, shaped, and sized to collect and hold the oilO.

The pan passageway 32 extends through at least one of the walls 38 andis entirely disposed between the inner pan surface 40 and the outer pansurface 42. In the depicted embodiment, the pan passageway 32 extendsthrough at least the bottom wall 38 b. It is envisioned, however, thatthe pan passageway 32 may also extend through the sidewalls 38 a.Irrespective of its exact location, the pan passageway 32 is configuredto carry the heat transfer fluid F in order to promote heat transferbetween the oil O (FIG. 1) disposed in the open cavity 44 and the heattransfer fluid F flowing through the pan passageway 32.

The pan passageway 32 may have a substantially U-shape and has an inlet46 in fluid communication with the fluid source 22 (FIG. 1) through theinput passageway 24 (FIG. 1). Therefore, the heat transfer fluid F canflow between the fluid source 22 and the pan passageway 32. Further, thepan passageway 32 includes an outlet 48 in fluid communication with theoutput passageway 34. Thus, the heat transfer fluid F can flow from thepan passageway 32 to the output passageway 34 after the heat has beentransferred between the oil O in the cavity 44 of the oil pan 16 and theheat transfer fluid F flowing through the pan passageway 32. Because theoil O in the oil pan 16 can be cooled by exchanging heat from the heattransfer fluid F, the engine assembly 12 does not need an oil cooler.Thus, the engine assembly 12 (and therefore the vehicle 10) does nothave an oil cooler for cooling the oil O in the oil pan 16.

With reference to FIG. 5, to heat or cool the oil O in the oil pan 16,the engine assembly 12 can be used in accordance with the method 100.The method 100 begins in step 102. In step 102, the heat transfer fluidF is heated or cooled before being introduced into the pan passageway32. To heat the heat transfer fluid F, heat can be transferred from theheat source 28 (e.g., exhaust manifold) to the heat transfer fluid Fwhile the heat transfer fluid F is flowing through the input passageway24 as discussed above. To cool the heat transfer fluid F, heat can betransferred from the heat transfer fluid F to the cooling source 30while the heat transfer fluid F flows through the input passageway 24.Then, the method 100 proceeds to step 104.

Step 104 entails introducing the heated or cooled heat transfer fluid Finto the pan passageway 32 while oil O is disposed in the cavity 44 ofthe oil pan 16. At this juncture, the heat transfer fluid F flowsthrough the pan passageway 32 from the inlet 46 to the outlet 48. Whilethe heat transfer fluid F flows through the pan passageway 32, heat istransferred between the oil O disposed in the cavity 44 of the oil pan16 and the heat transfer fluid F flowing through the pan passageway 32in order to cool or warm up the oil O. Then, the method 100 continues tostep 106.

In step 106, the heat transfer fluid F flows out of the pan passageway32 through the outlet 48 and into the output passageway 34. At thispoint, the heat transfer fluid F may be directed back to the inputpassageway 24 in order to be recycled.

While the best modes for carrying out the teachings have been describedin detail, those familiar with the art to which this disclosure relateswill recognize various alternative designs and embodiments forpracticing the teachings within the scope of the appended claims.

1. An engine assembly, comprising: an oil pan including an oil pan body,wherein the oil pan body includes: an inner pan surface defining acavity configured to collect oil; an outer pan surface opposite theinner pan surface; and a pan passageway formed by the oil pan body,wherein the pan passageway is disposed between the inner pan surface andthe outer pan surface; and wherein the pan passageway is configured tocarry a heat transfer fluid in order to transfer heat between the oildisposed in the cavity and the heat transfer fluid.
 2. The engineassembly of claim 1, further comprising a fluid source including theheat transfer fluid.
 3. The engine assembly of claim 2, furthercomprising a fluid transfer pump in fluid communication with the fluidsource such that the fluid transfer pump is configured to move the heattransfer fluid from the fluid source to the pan passageway.
 4. Theengine assembly of claim 1, wherein the engine assembly is characterizedby the absence of an oil cooler.
 5. The engine assembly of claim 1,further comprising an input passageway in fluid communication with thepan passageway such that the heat transfer fluid is capable of flowingfrom the input passageway to the pan passageway, wherein the inputpassageway is outside the oil pan.
 6. The engine assembly of claim 5,further comprising a heat source in thermal communication with the inputpassageway such that the heat source is capable of heating the heattransfer fluid flowing through the input passageway.
 7. The engineassembly of claim 6, wherein the heat source is an exhaust manifold. 8.The engine assembly of claim 6, wherein the heat source is aturbocharger.
 9. The engine assembly of claim 6, wherein the heat sourceis an exhaust gas recirculation system.
 10. The engine assembly of claim6, wherein the heat source is an engine block.
 11. The engine assemblyof claim 6, wherein the heat source is an engine head.
 12. The engineassembly of claim 5, further comprising a cooling system in thermalcommunication with the input passageway such that cooling system iscapable of cooling the heat transfer fluid flowing through the inputpassageway.
 13. An oil pan, comprising: an oil pan body having an innerpan surface and an outer pan surface opposite the inner pan surface,wherein the inner pan surface defines an open cavity configured tocollect oil, the oil pan defines a pan passageway disposed between theinner pan surface and the outer pan surface, and the pan passageway isconfigured to receive a heat transfer fluid.
 14. The oil pan of claim13, wherein the oil pan body includes a plurality of sidewalls, and abottom wall interconnecting the sidewalls, and the pan passagewayextends at least through the bottom wall.
 15. The oil pan of claim 13,wherein the pan passageway includes an inlet in fluid communication witha fluid source having the heat transfer fluid such that the heattransfer fluid is capable of flowing from the fluid source to the panpassageway through the inlet.
 16. A method of exchanging heat between aheat transfer fluid and oil disposed in an oil pan, the methodcomprising: introducing the heat transfer fluid into a pan passageway ofthe oil pan while the oil is in the oil pan, wherein the oil panincludes an oil pan body, the oil pan body defines an inner pan surfaceand an outer pan surface opposite the inner pan surface, and the innerpan surface defines a cavity holding the oil, and the pan passagewayextends through the oil pan body between the inner pan surface and theouter pan surface.
 17. The method of claim 16, further comprisingheating the heat transfer fluid before introducing the heat transferfluid through the pan passageway.
 18. The method of claim 17, whereinheating the heat transfer fluid includes transferring heat from anexhaust manifold to the heat transfer fluid.
 19. The method of claim 16,further comprising cooling the heat transfer fluid before introducingthe heat transfer fluid through the pan passageway.
 20. The method ofclaim 16, wherein the oil pan includes a bottom wall, and the panpassageway extend at least through the bottom wall.